THE VIRGINIAN-PILOT
Copyright (c) 1994, Landmark Communications, Inc.
DATE: Saturday, December 3, 1994 TAG: 9412030240
SECTION: BUSINESS PAGE: D1 EDITION: FINAL
SOURCE: BY JAMES SCHULTZ, STAFF WRITER
DATELINE: HAMPTON LENGTH: Medium: 77 lines
They flew right into the teeth of the worst weather they could find. Not once in 160 times did anything happen to their airplane. But 24 times, alarms rebounded through the cockpit as heavy wind and rain slashed at fuselage and wings.
``Let's put it this way,'' said Roland L. Bowles, former wind-shear program manager at NASA Langley Research Center. ``This was not routine flying.''
From Langley's less-than-ordinary flights has come a device to warn pilots of a potentially fatal atmospheric disturbance known as wind shear. Earlier this week, a Continental Airlines airplane became the first commercial craft to carry a wind-shear warning instrument.
The equipment on the Continental plane was the direct result of seven years of research conducted from 1986 through 1993 by NASA Langley in cooperation with the Federal Aviation Administration. By the end of 1995, some form of wind-shear detection will be mandatory for all U.S. commercial passenger aircraft.
``When the fleet is fully equipped, wind-shear accidents will be significantly reduced,'' Bowles said. ``We felt from the outset that this technology had a high payoff. Lives will be saved.''
Since 1964, at least 30 crashes or other mishaps have been attributed to wind shear, according to figures compiled by the National Transportation Safety Board. More than 500 people have been killed and 200 injured in those accidents.
Wind shear occurs when powerful downdrafts of air, or ``microbursts,'' cascade to Earth like water gushing from a gigantic faucet. When these strong torrents reach the ground they spread out in all directions. Planes unlucky enough to be caught in a wind-shear's down-splash while taking off or landing can lose aerodynamic lift and crash.
Langley scientists evaluated three different kinds of wind-shear warning systems in tests at their Hampton labs and while airborne over Orlando, Fla., and Denver, Colo. They flew in a specially outfitted and strengthened Boeing 737.
The system they chose is called microwave Doppler radar. It uses radio microwaves to determine speed and direction of raindrops in storm clouds. Pilots should adapt easily to the new equipment, since cockpit readouts are similar to those of other on-board weather radars.
``It's like putting headlights on a car at night,'' said Bob Flocke , a spokesman for the Air Line Pilots Association. ``Anything like this that will improve safety we're 100 percent behind. We think it's great.''
A new generation of ground-based weather radars are being installed at all major U.S. airports, a process that won't be completed for several more years. While the new on-ground radars can detect microbursts once they occur, they are not particularly good at predicting wind shear, nor can they immediately signal each and every plane of impending hazard.
Because the new device is mounted inside airplanes, pilots will receive split-second information on wind speed, intensity and direction so that they can fly safely through or avoid wind shear altogether.
One of the two other detection systems Langley researchers studied was an infrared type that measured temperature changes in front of the airplane during flight. The other employed bursts of laser light to determine the speed of atmospheric dust and minute particles called aerosols to detect wind changes.
Of the two, NASA's Bowles said, the laser system is the most promising and may end up as the successor to the microwave radar system sometime in the 21st century.
Three companies are making versions of the approved device. According to Bowles, some 1,000 are on order. The instruments will retail for between $70,000 and $75,000.
Bowles, who remains at Langley to lead research into airplane safety, said the Langley team couldn't be happier to see the project end the way it did.
``We all went home extremely excited by what has happened,'' he said. ``We made a significant difference in airline safety. To see the technology come to maturity and see it integrated into an operational system is icing on the cake.'' by CNB